Calculate DO Saturation

WRDB can add computed values of DO saturation, DO deficit, and
percent saturation to a Working table. DO saturation, expressed in
mg/L, depends on water temperature and salinity. WRDB uses the 1985
APHA formula assuming fresh water and mean sea level. The formula is:

DO deficit is simply the difference between the observed DO and
computed DO saturation concentration. Percent saturation is the ratio
of observed DO to DO saturation value, expressed as a percent.

To compute these values, you must first compile a set of simultaneous
observations of DO (mg/L) and water temperature (ºC) using one
of the methods described in Output
Data Overview. You may compile the data from several sources and
place them in a Working table using the Save
to Table function. PCodes in that table other than DO and
temperature will be ignored. Prior to computing the values, open the
Working table where the input data have been compiled and computed
values will be placed. Select Edit | Calculate | DO Saturation to
start the step-by-step process of performing the calculations:

Use this screen to specify the PCodes that correspond to the input
data (DO and temperature) and the PCodes for values to be computed.
The drop-down lists contain all current valid PCodes in your
Projects PCode Support table. If you dont already have
PCodes defined for the calculated parameters, click Cancel and add
them to the Support table. You may choose "None" to
suppress calculation of one or more parameters. Finally, select the
desired CCode to be assigned to each computed value from the list
taken from your CCode Support table. Click Next
to continue and see the next screen:

This screen shows you a list of simultaneous DO and temperature
values found in the Working table that will be processed. Click
Finish to see the final confirmation screen:

To avoid duplicating data, all data in the selected Working table
having the specified DO saturation PCodes will be deleted before the
newly computed values are added.